Mills and other fragmenting devices are commonly known to be used to grind and pulverize solid matter. For various reasons, any number of different types of solid material may require particle size reduction. Among those different types of material are agricultural products such as wheat and corn. Of equal importance, however, is waste matter that must be reduced in size before being finally disposed. Medical waste must often times be reduced before disposal to prevent it from attracting attention or presenting a hazard to those that must handle it. Furthermore, it protects the public that may subsequently contact the waste, either intentionally, or inadvertently.
Depending upon the nature of the waste to be reduced, hammer mills using hammer pins have been used to pulverize hard materials thereby making the materials easier to dispose. Other mills have utilized a series of saw blades to shred more pliable materials such as fabric, paper, and plastic. Heretofore, the two have not been combined.
Because of increased public concern regarding communicable diseases, statutes and administrative rules and regulations have issued that require hospitals that dispose of waste in landfills to process it into an unrecognizable form prior to public disposal. One method is to use a mill to process the waste. U.S. patents that have issued concerning mills used for processing hospital waste include U.S. Pat. No. 3,389,864 to Topinka for Waste Disposal Unit and U.S. Pat. No. 3,929,295 to Montalbano for Apparatus For Destroying Syringes and Like Articles.
U.S. Pat. No. 3,389,864 includes the disclosure of a waste disposal unit designed to dispose of fabrics. The waste disposal unit includes a housing. A pair of cylindrical rollers with a series of blades extending from their respective circumferences is positioned inside the housing. Adjacent to each cylindrical roller is a raking bar. The raking bar clears debris that accumulates on the cylindrical roller. Each cylindrical roller is positioned so that a passageway exists between the two rollers.
U.S. Pat. No. 3,929,295 includes disclosure of a waste disposal apparatus unit for syringes contained within a housing. Attached to the top of the housing is a storage unit used to hold syringes that are about to be destroyed. Inside the housing is an elongated bar having several circular saws positioned down the length of the elongated bar. A series of stationary blades are placed interstitially between the circular saws separating one from the others. As syringes are fed into the apparatus, a chute guides the syringes to the rear of the saws. The saws rotate thereby catching and propelling the syringe against the series of stationary blades. As a result, the syringes emerge from the front side of the saw in a dismembered state.
Examining these devices reveals significant shortcomings when the simultaneous reduction of commingled rigid and pliable waste is contemplated. Because known disposal units have specialized functions with respect to rigid and pliable solid waste, the waste must be separated prior to disposal. Separating waste requires extra work, which translates into additional time and money. Furthermore, space must be allocated for storing the segregated waste prior to disposal.
In the more particular instance of medical waste, workers may be exposed to such incurable and life-threatening diseases as Acquired Immunity Deficiency Syndrome (AIDS) and hepatitis during the pre-sorting process. In the specific example of syringe disposal, most devices require manual loading. The manual loading process consumes inordinate amounts of time and directly and repeatedly exposes the disposal worker handling the syringes to the risk of puncturing themselves with contaminated needles.
A need exists for a waste disposal apparatus for hospitals and others that can dispose of not only pliable materials, but hard objects as well. In the example of a hospital, such a device should be able to handle large loads of unsegregated hospital waste and process it in such a manner that the waste is unrecognizable in a land fill. Still further, a disposal device is needed that can reduce moist and liquid soaked materials without binding or clogging. Further yet, the device should minimize the workers' exposure to the waste until it is processed into a innocuous form. Not only are complete disposal systems sought, but improved components for achieving the various size reductions are also needed.